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1.
JCO Clin Cancer Inform ; 8: e2300251, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38709234

RESUMO

PURPOSE: The emergence of large real-world clinical databases and tools to mine electronic medical records has allowed for an unprecedented look at large data sets with clinical and epidemiologic correlates. In clinical cancer genetics, real-world databases allow for the investigation of prevalence and effectiveness of prevention strategies and targeted treatments and for the identification of barriers to better outcomes. However, real-world data sets have inherent biases and problems (eg, selection bias, incomplete data, measurement error) that may hamper adequate analysis and affect statistical power. METHODS: Here, we leverage a real-world clinical data set from a large health network for patients with breast cancer tested for variants in BRCA1 and BRCA2 (N = 12,423). We conducted data cleaning and harmonization, cross-referenced with publicly available databases, performed variant reassessment and functional assays, and used functional data to inform a variant's clinical significance applying American College of Medical Geneticists and the Association of Molecular Pathology guidelines. RESULTS: In the cohort, White and Black patients were over-represented, whereas non-White Hispanic and Asian patients were under-represented. Incorrect or missing variant designations were the most significant contributor to data loss. While manual curation corrected many incorrect designations, a sizable fraction of patient carriers remained with incorrect or missing variant designations. Despite the large number of patients with clinical significance not reported, original reported clinical significance assessments were accurate. Reassessment of variants in which clinical significance was not reported led to a marked improvement in data quality. CONCLUSION: We identify the most common issues with BRCA1 and BRCA2 testing data entry and suggest approaches to minimize data loss and keep interpretation of clinical significance of variants up to date.


Assuntos
Proteína BRCA1 , Proteína BRCA2 , Neoplasias da Mama , Mutação em Linhagem Germinativa , Sistema de Registros , Humanos , Neoplasias da Mama/genética , Neoplasias da Mama/epidemiologia , Feminino , Proteína BRCA1/genética , Proteína BRCA2/genética , Pessoa de Meia-Idade , Predisposição Genética para Doença , Adulto , Registros Eletrônicos de Saúde , Idoso
3.
NPJ Genom Med ; 9(1): 19, 2024 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-38443389

RESUMO

Survival from ovarian cancer depends on the resection status after primary surgery. We performed genome-wide association analyses for resection status of 7705 ovarian cancer patients, including 4954 with high-grade serous carcinoma (HGSOC), to identify variants associated with residual disease. The most significant association with resection status was observed for rs72845444, upstream of MGMT, in HGSOC (p = 3.9 × 10-8). In gene-based analyses, PPP2R5C was the most strongly associated gene in HGSOC after stage adjustment. In an independent set of 378 ovarian tumours from the AGO-OVAR 11 study, variants near MGMT and PPP2R5C correlated with methylation and transcript levels, and PPP2R5C mRNA levels predicted progression-free survival in patients with residual disease. MGMT encodes a DNA repair enzyme, and PPP2R5C encodes the B56γ subunit of the PP2A tumour suppressor. Our results link heritable variation at these two loci with resection status in HGSOC.

4.
Am J Hum Genet ; 111(3): 584-593, 2024 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-38417439

RESUMO

Variants of uncertain significance (VUSs) in BRCA2 are a common result of hereditary cancer genetic testing. While more than 4,000 unique VUSs, comprised of missense or intronic variants, have been identified in BRCA2, the few missense variants now classified clinically as pathogenic or likely pathogenic are predominantly located in the region encoding the C-terminal DNA binding domain (DBD). We report on functional evaluation of the influence of 462 BRCA2 missense variants affecting the DBD on DNA repair activity of BRCA2 using a homology-directed DNA double-strand break repair assay. Of these, 137 were functionally abnormal, 313 were functionally normal, and 12 demonstrated intermediate function. Comparisons with other functional studies of BRCA2 missense variants yielded strong correlations. Sequence-based in silico prediction models had high sensitivity, but limited specificity, relative to the homology-directed repair assay. Combining the functional results with clinical and genetic data in an American College of Medical Genetics (ACMG)/Association for Molecular Pathology (AMP)-like variant classification framework from a clinical testing laboratory, after excluding known splicing variants and functionally intermediate variants, classified 431 of 442 (97.5%) missense variants (129 as pathogenic/likely pathogenic and 302 as benign/likely benign). Functionally abnormal variants classified as pathogenic by ACMG/AMP rules were associated with a slightly lower risk of breast cancer (odds ratio [OR] 5.15, 95% confidence interval [CI] 3.43-7.83) than BRCA2 DBD protein truncating variants (OR 8.56, 95% CI 6.03-12.36). Overall, functional studies of BRCA2 variants using validated assays substantially improved the variant classification yield from ACMG/AMP models and are expected to improve clinical management of many individuals found to harbor germline BRCA2 missense VUS.


Assuntos
Neoplasias da Mama , Predisposição Genética para Doença , Humanos , Feminino , Proteína BRCA2/genética , Testes Genéticos , Mutação de Sentido Incorreto/genética , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Células Germinativas/patologia , DNA
5.
HGG Adv ; 4(4): 100240, 2023 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-37718511

RESUMO

Carriers of BRCA1 germline pathogenic variants are at substantially higher risk of developing breast and ovarian cancer than the general population. Accurate identification of at-risk individuals is crucial for risk stratification and the implementation of targeted preventive and therapeutic interventions. Despite significant progress in variant classification efforts, a sizable portion of reported BRCA1 variants remain as variants of uncertain clinical significance (VUSs). Variants leading to premature protein termination and loss of essential functional domains are typically classified as pathogenic. However, the impact of frameshift variants that result in an extended incorrect terminus is not clear. Using validated functional assays, we conducted a systematic functional assessment of 17 previously reported BRCA1 extended incorrect terminus variants (EITs) and concluded that 16 constitute loss-of-function variants. This suggests that most EITs are likely to be pathogenic. However, one variant, c.5578dup, displayed a protein expression level, affinity to known binding partners, and activity in transcription and homologous recombination assays comparable to the wild-type BRCA1 protein. Twenty-three additional carriers of c.5578dup were identified at a US clinical diagnostic lab and assessed using a family history likelihood model providing, in combination with the functional data, a likely benign interpretation. These results, consistent with family history data in the current study and available data from ClinVar, indicate that most, but not all, BRCA1 variants leading to an extended incorrect terminus constitute loss-of-function variants and underscore the need for comprehensive assessment of individual variants.


Assuntos
Predisposição Genética para Doença , Neoplasias Ovarianas , Feminino , Humanos , Proteína C , Proteína BRCA1/genética , Neoplasias Ovarianas/epidemiologia , Mutação em Linhagem Germinativa/genética
6.
G3 (Bethesda) ; 13(2)2023 02 09.
Artigo em Inglês | MEDLINE | ID: mdl-36454217

RESUMO

Intraductal papillary mucinous neoplasms (IPMNs) are precursor lesions to pancreatic ductal adenocarcinoma that are challenging to manage due to limited imaging, cytologic, and molecular markers that accurately classify lesions, grade of dysplasia, or focus of invasion preoperatively. The objective of this pilot study was to determine the frequency and type of DNA mutations in a cohort of surgically resected, pathologically confirmed IPMN, and to determine if concordant mutations are detectable in paired pretreatment plasma samples. Formalin-fixed paraffin-embedded (FFPE) tissue from 46 surgically resected IPMNs (31 low-grade, 15 high-grade) and paired plasma from a subset of 15 IPMN cases (10 low-grade, 5 high-grade) were subjected to targeted mutation analysis using a QIAseq Targeted DNA Custom Panel. Common driver mutations were detected in FFPE from 44 of 46 (95.6%) IPMN cases spanning all grades; the most common DNA mutations included: KRAS (80%), RNF43 (24%), and GNAS (43%). Of note, we observed a significant increase in the frequency of RNF43 mutations from low-grade to high-grade IPMNs associated or concomitant with invasive carcinoma (trend test, P = 0.01). Among the subset of cases with paired plasma, driver mutations identified in the IPMNs were not detected in circulation. Overall, our results indicate that mutational burden for IPMNs is a common occurrence, even in low-grade IPMNs. Furthermore, although blood-based biopsies are an attractive, noninvasive method for detecting somatic DNA mutations, the QIAseq panel was not sensitive enough to detect driver mutations that existed in IPMN tissue using paired plasma in the volume we were able to retrieve for this retrospective study.


Assuntos
Neoplasias Císticas, Mucinosas e Serosas , Neoplasias Intraductais Pancreáticas , Neoplasias Pancreáticas , Humanos , Neoplasias Intraductais Pancreáticas/genética , Neoplasias Intraductais Pancreáticas/patologia , Projetos Piloto , Estudos Retrospectivos , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/patologia , Neoplasias Pancreáticas/cirurgia , Mutação
7.
bioRxiv ; 2023 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-38168194

RESUMO

Germline BRCA2 loss-of function (LOF) variants identified by clinical genetic testing predispose to breast, ovarian, prostate and pancreatic cancer. However, variants of uncertain significance (VUS) (n>4000) limit the clinical use of testing results. Thus, there is an urgent need for functional characterization and clinical classification of all BRCA2 variants. Here we report on comprehensive saturation genome editing-based functional characterization of 97% of all possible single nucleotide variants (SNVs) in the BRCA2 DNA Binding Domain hotspot for pathogenic missense variants that is encoded by exons 15 to 26. The assay was based on deep sequence analysis of surviving endogenously targeted haploid cells. A total of 7013 SNVs were characterized as functionally abnormal (n=955), intermediate/uncertain, or functionally normal (n=5224) based on 95% agreement with ClinVar known pathogenic and benign standards. Results were validated relative to batches of nonsense and synonymous variants and variants evaluated using a homology directed repair (HDR) functional assay. Breast cancer case-control association studies showed that pooled SNVs encoding functionally abnormal missense variants were associated with increased risk of breast cancer (odds ratio (OR) 3.89, 95%CI: 2.77-5.51). In addition, 86% of tumors associated with abnormal missense SNVs displayed loss of heterozygosity (LOH), whereas 26% of tumors with normal variants had LOH. The functional data were added to other sources of information in a ClinGen/ACMG/AMP-like model and 700 functionally abnormal SNVs, including 220 missense SNVs, were classified as pathogenic or likely pathogenic, while 4862 functionally normal SNVs, including 3084 missense SNVs, were classified as benign or likely benign. These classified variants can now be used for risk assessment and clinical care of variant carriers and the remaining functional scores can be used directly for clinical classification and interpretation of many additional variants. Summary: Germline BRCA2 loss-of function (LOF) variants identified by clinical genetic testing predispose to several types of cancer. However, variants of uncertain significance (VUS) limit the clinical use of testing results. Thus, there is an urgent need for functional characterization and clinical classification of all BRCA2 variants to facilitate current and future clinical management of individuals with these variants. Here we show the results from a saturation genome editing (SGE) and functional analysis of all possible single nucleotide variants (SNVs) from exons 15 to 26 that encode the BRCA2 DNA Binding Domain hotspot for pathogenic missense variants. The assay was based on deep sequence analysis of surviving endogenously targeted human haploid HAP1 cells. The assay was calibrated relative to ClinVar known pathogenic and benign missense standards and 95% prevalence thresholds for functionally abnormal and normal variants were identified. Thresholds were validated based on nonsense and synonymous variants. SNVs encoding functionally abnormal missense variants were associated with increased risks of breast and ovarian cancer. The functional assay results were integrated into a ClinGen/ACMG/AMP-like model for clinical classification of the majority of BRCA2 SNVs as pathogenic/likely pathogenic or benign/likely benign. The classified variants can be used for improved clinical management of variant carriers.

8.
J Biol Chem ; 298(11): 102550, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36183837

RESUMO

BRCA1/2-deficient ovarian carcinoma (OC) has been shown to be particularly sensitive to poly (ADP-ribose) polymerase inhibitors (PARPis). Furthermore, BRCA1/2 mutation status is currently used as a predictive biomarker for PARPi therapy. Despite providing a major clinical benefit to the majority of patients, a significant proportion of BRCA1/2-deficient OC tumors do not respond to PARPis for reasons that are incompletely understood. Using an integrated chemical, phospho- and ADP-ribosylation proteomics approach, we sought here to develop additional mechanism-based biomarker candidates for PARPi therapy in OC and identify new targets for combination therapy to overcome primary resistance. Using chemical proteomics with PARPi baits in a BRCA1-isogenic OC cell line pair, as well as patient-derived BRCA1-proficient and BRCA1-deficient tumor samples, and subsequent validation by coimmunoprecipitation, we showed differential PARP1 and PARP2 protein complex composition in PARPi-sensitive, BRCA1-deficient UWB1.289 (UWB) cells compared to PARPi-insensitive, BRCA1-reconstituted UWB1.289+BRCA1 (UWB+B) cells. In addition, global phosphoproteomics and ADP-ribosylation proteomics furthermore revealed that the PARPi rucaparib induced the cell cycle pathway and nonhomologous end joining (NHEJ) pathway in UWB cells but downregulated ErbB signaling in UWB+B cells. In addition, we observed AKT PARylation and prosurvival AKT-mTOR signaling in UWB+B cells after PARPi treatment. Consistently, we found the synergy of PARPis with DNAPK or AKT inhibitors was more pronounced in UWB+B cells, highlighting these pathways as actionable vulnerabilities. In conclusion, we demonstrate the combination of chemical proteomics, phosphoproteomics, and ADP-ribosylation proteomics can identify differential PARP1/2 complexes and diverse, but actionable, drug compensatory signaling in OC.


Assuntos
Neoplasias Ovarianas , Inibidores de Poli(ADP-Ribose) Polimerases , Humanos , Feminino , Inibidores de Poli(ADP-Ribose) Polimerases/farmacologia , Proteômica , Proteínas Proto-Oncogênicas c-akt , Resistencia a Medicamentos Antineoplásicos , Linhagem Celular Tumoral , Proteína BRCA1/genética , Proteína BRCA1/metabolismo , Neoplasias Ovarianas/tratamento farmacológico , Neoplasias Ovarianas/genética , Neoplasias Ovarianas/patologia
9.
Sci Rep ; 12(1): 16203, 2022 09 28.
Artigo em Inglês | MEDLINE | ID: mdl-36171434

RESUMO

BRCA1 (Breast Cancer 1, early onset) is linked to breast and ovarian cancer predisposition. Still, the risks conferred by a significant portion of BRCA1 variants identified in the population remains unknown. Most of these variants of uncertain significance are missense alterations. However, the functional implications of small in-frame deletions and/or insertions (indels) are also difficult to predict. Our group has previously evaluated the functional impact of 347 missense variants using an extensively validated transcriptional activity assay. Here we show a systematic assessment of 30 naturally occurring in-frame indels located at the C-terminal region of BRCA1. We identified positions sensitive and tolerant to alterations, expanding the knowledge of structural determinants of BRCA1 function. We further designed and assessed the impact of four single codon deletions in the tBRCT linker region and six nonsense variants at the C-terminus end of BRCA1. Amino acid substitutions, deletions or insertions in the disordered region do not significantly impact activity and are not likely to constitute pathogenic alleles. On the other hand, a sizeable fraction of in-frame indels at the BRCT domain significantly impact function. We then use a Bayesian integrative statistical model to derive the probability of pathogenicity for each variant. Our data highlights the importance of assessing the impact of small in-frame indels in BRCA1 to improve risk assessment and clinical decisions for carriers.


Assuntos
Neoplasias da Mama , Neoplasias Ovarianas , Alelos , Substituição de Aminoácidos , Proteína BRCA1/metabolismo , Teorema de Bayes , Feminino , Genes BRCA1 , Predisposição Genética para Doença , Humanos , Mutação de Sentido Incorreto , Neoplasias Ovarianas/genética
10.
Front Pharmacol ; 13: 935995, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35837282

RESUMO

BRCA1 is a major tumor suppressor that functions in the accurate repair of DNA double-strand breaks via homologous recombination (HR). Nonsense mutations in BRCA1 lead to inactive truncated protein products and are associated with high risk of breast and ovarian cancer. These mutations generate premature termination codons (PTCs). Different studies have shown that aminoglycosides can induce PTC suppression by promoting stop codon readthrough and restoring full-length (FL) protein expression. The use of these compounds has been studied in clinical trials for genetic diseases such as cystic fibrosis and Duchenne muscular dystrophy, with encouraging results. Here we show proof-of-concept data demonstrating that the aminoglycoside G418 can induce BRCA1 PTC readthrough and restore FL protein synthesis and function. We first demonstrate that G418 treatment restores BRCA1 FL protein synthesis in HCC1395, a human breast tumor cell line carrying the R1751X mutation. HCC1395 cells treated with G418 also recover HR DNA repair and restore cell cycle checkpoint activation. A set of naturally occurring BRCA1 nonsense variants encoding different PTCs was evaluated in a GFP C-terminal BRCA1 construct model and BRCA1 PTC readthrough levels vary depending on the stop codon context. Because PTC readthrough could generate FL protein carrying pathogenic missense mutations, variants representing the most probable acquired amino acid substitutions in consequence of readthrough were functionally assessed by a validated transcription activation assay. Overall, this is the first study that evaluates the readthrough of PTC variants with clinical relevance in the breast and ovarian cancer-predisposing gene BRCA1.

11.
Clin Cancer Res ; 28(17): 3742-3751, 2022 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-35736817

RESUMO

PURPOSE: The identification of variants of uncertain significance (VUS) in the BRCA1 and BRCA2 genes by hereditary cancer testing poses great challenges for the clinical management of variant carriers. The ACMG/AMP (American College of Medical Genetics and Genomics/Association for Molecular Pathology) variant classification framework, which incorporates multiple sources of evidence, has the potential to establish the clinical relevance of many VUS. We sought to classify the clinical relevance of 133 single-nucleotide substitution variants encoding missense variants in the DNA-binding domain (DBD) of BRCA2 by incorporating results from a validated functional assay into an ACMG/AMP-variant classification model from a hereditary cancer-testing laboratory. EXPERIMENTAL DESIGN: The 133 selected VUS were evaluated using a validated homology-directed double-strand DNA break repair (HDR) functional assay. Results were combined with clinical and genetic data from variant carriers in a rules-based variant classification model for BRCA2. RESULTS: Of 133 missense variants, 44 were designated as non-functional and 89 were designated as functional in the HDR assay. When combined with genetic and clinical information from a single diagnostic laboratory in an ACMG/AMP-variant classification framework, 66 variants previously classified by the diagnostic laboratory were correctly classified, and 62 of 67 VUS (92.5%) were reclassified as likely pathogenic (n = 22) or likely benign (n = 40). In total, 44 variants were classified as pathogenic/likely pathogenic, 84 as benign/likely benign, and 5 remained as VUS. CONCLUSIONS: Incorporation of HDR functional analysis into an ACMG/AMP framework model substantially improves BRCA2 VUS re-classification and provides an important tool for determining the clinical relevance of individual BRCA2 VUS.


Assuntos
Neoplasias da Mama , Genes BRCA2 , Feminino , Humanos , Proteína BRCA2/genética , Neoplasias da Mama/genética , Predisposição Genética para Doença , Testes Genéticos/métodos , Variação Genética
12.
NPJ Genom Med ; 7(1): 35, 2022 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-35665744

RESUMO

Loss-of-function variants in the BRCA1 and BRCA2 susceptibility genes predispose carriers to breast and/or ovarian cancer. The use of germline testing panels containing these genes has grown dramatically, but the interpretation of the results has been complicated by the identification of many sequence variants of undefined cancer relevance, termed "Variants of Uncertain Significance (VUS)." We have developed functional assays and a statistical model called VarCall for classifying BRCA1 and BRCA2 VUS. Here we describe a multifactorial extension of VarCall, called VarCall XT, that allows for co-analysis of multiple forms of genetic evidence. We evaluated the accuracy of models defined by the combinations of functional, in silico protein predictors, and family data for VUS classification. VarCall XT classified variants of known pathogenicity status with high sensitivity and specificity, with the functional assays contributing the greatest predictive power. This approach could be used to identify more patients that would benefit from personalized cancer risk assessment and management.

13.
Clin Cancer Res ; 28(15): 3342-3355, 2022 08 02.
Artigo em Inglês | MEDLINE | ID: mdl-35653140

RESUMO

PURPOSE: To identify molecular predictors of grade 3/4 neutropenic or leukopenic events (NLE) after chemotherapy using a genome-wide association study (GWAS). EXPERIMENTAL DESIGN: A GWAS was performed on patients in the phase III chemotherapy study SUCCESS-A (n = 3,322). Genotyping was done using the Illumina HumanOmniExpress-12v1 array. Findings were functionally validated with cell culture models and the genotypes and gene expression of possible causative genes were correlated with clinical treatment response and prognostic outcomes. RESULTS: One locus on chromosome 16 (rs4784750; NLRC5; P = 1.56E-8) and another locus on chromosome 13 (rs16972207; TNFSF13B; P = 3.42E-8) were identified at a genome-wide significance level. Functional validation revealed that expression of these two genes is altered by genotype-dependent and chemotherapy-dependent activity of two transcription factors. Genotypes also showed an association with disease-free survival in patients with an NLE. CONCLUSIONS: Two loci in NLRC5 and TNFSF13B are associated with NLEs. The involvement of the MHC I regulator NLRC5 implies the possible involvement of immuno-oncological pathways.


Assuntos
Neoplasias da Mama , Leucopenia , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/genética , Feminino , Loci Gênicos , Predisposição Genética para Doença , Estudo de Associação Genômica Ampla , Genótipo , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/genética , Leucopenia/induzido quimicamente , Leucopenia/genética , Polimorfismo de Nucleotídeo Único
14.
Hum Mutat ; 43(10): 1396-1407, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35762214

RESUMO

Chordoma is a rare bone tumor with genetic risk factors largely unknown. We conducted a whole-exome sequencing (WES) analysis of germline DNA from 19 familial chordoma cases in five pedigrees and 137 sporadic chordoma patients and identified 17 rare germline variants in PALB2 and BRCA2, whose products play essential roles in homologous recombination (HR) and tumor suppression. One PALB2 variant showed disease cosegregation in a family with four affected people or obligate gene carrier. Chordoma cases had a significantly increased burden of rare variants in both genes when compared to population-based controls. Four of the six PALB2 variants identified from chordoma patients modestly affected HR function and three of the 11 BRCA2 variants caused loss of function in experimental assays. These results, together with previous reports of abnormal morphology and Brachyury expression of the notochord in Palb2 knockout mouse embryos and genomic signatures associated with HR defect and HR gene mutations in advanced chordomas, suggest that germline mutations in PALB2 and BRCA2 may increase chordoma susceptibility. Our data shed light on the etiology of chordoma and support the previous finding that PARP-1 inhibitors may be a potential therapy for some chordoma patients.


Assuntos
Proteína BRCA2 , Neoplasias da Mama , Cordoma , Proteína do Grupo de Complementação N da Anemia de Fanconi , Animais , Proteína BRCA2/genética , Neoplasias da Mama/genética , Cordoma/genética , Proteína do Grupo de Complementação N da Anemia de Fanconi/genética , Feminino , Genes BRCA2 , Predisposição Genética para Doença , Mutação em Linhagem Germinativa , Humanos , Camundongos
15.
J Med Virol ; 94(7): 3442-3447, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35229315

RESUMO

Human pegivirus-1 (HPgV-1) is a member of the Flaviviridae family and the Pegivirus genus. Despite having been discovered 25 years ago, there is still much to know regarding HPgV-1 clinical impact, as this virus is currently not associated with any pathology. Yet, HPgV-1 prevalence and molecular characterization are still unknown in many countries, including Portugal. To fill in this knowledge gap, this study aimed to determine the occurrence and molecular characterization of HPgV-1 in a group of healthy blood donors from the north of Portugal. Blood samples from 465 Portuguese blood donors were collected from a major Hospital Center in the north of Portugal. RNA was extracted and an initial nested RT-PCR was performed targeting the conserved 5'-untranslated region  region of the HPgV-1 genome. A second nested RT-PCR targeting the E2 region was performed for genotyping. Only one sample tested positive for HPgV-1 RNA, resulting in a prevalence of approximately 0.22%. Phylogenetic analyses confirmed the characterization as genotype 2, the most prevalent in Europe.


Assuntos
Infecções por Flaviviridae , Flaviviridae , Vírus GB C , Doadores de Sangue , Flaviviridae/genética , Infecções por Flaviviridae/epidemiologia , Vírus GB C/genética , Voluntários Saudáveis , Humanos , Filogenia , Portugal/epidemiologia , Prevalência , RNA , RNA Viral/genética , Viremia/epidemiologia
17.
Cell Chem Biol ; 29(2): 202-214.e7, 2022 02 17.
Artigo em Inglês | MEDLINE | ID: mdl-34329582

RESUMO

PARP inhibitors (PARPis) display single-agent anticancer activity in small cell lung cancer (SCLC) and other neuroendocrine tumors independent of BRCA1/2 mutations. Here, we determine the differential efficacy of multiple clinical PARPis in SCLC cells. Compared with the other PARPis rucaparib, olaparib, and niraparib, talazoparib displays the highest potency across SCLC, including SLFN11-negative cells. Chemical proteomics identifies PARP16 as a unique talazoparib target in addition to PARP1. Silencing PARP16 significantly reduces cell survival, particularly in combination with PARP1 inhibition. Drug combination screening reveals talazoparib synergy with the WEE1/PLK1 inhibitor adavosertib. Global phosphoproteomics identifies disparate effects on cell-cycle and DNA damage signaling thereby illustrating underlying mechanisms of synergy, which is more pronounced for talazoparib than olaparib. Notably, silencing PARP16 further reduces cell survival in combination with olaparib and adavosertib. Together, these data suggest that PARP16 contributes to talazoparib's overall mechanism of action and constitutes an actionable target in SCLC.


Assuntos
Antineoplásicos/farmacologia , Proteínas de Ciclo Celular/antagonistas & inibidores , Ftalazinas/farmacologia , Inibidores de Poli(ADP-Ribose) Polimerases/farmacologia , Poli(ADP-Ribose) Polimerases/metabolismo , Proteínas Tirosina Quinases/antagonistas & inibidores , Idoso , Antineoplásicos/química , Ciclo Celular/efeitos dos fármacos , Proteínas de Ciclo Celular/metabolismo , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Dano ao DNA , Ensaios de Seleção de Medicamentos Antitumorais , Feminino , Humanos , Masculino , Ftalazinas/química , Inibidores de Poli(ADP-Ribose) Polimerases/química , Proteínas Tirosina Quinases/metabolismo , Células Tumorais Cultivadas
18.
Eur J Hum Genet ; 30(4): 465-473, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-34803163

RESUMO

Genome wide-association studies (GWAS) have established over 400 breast cancer risk loci defined by common single nucleotide polymorphisms (SNPs), including several associated with estrogen-receptor (ER)-negative disease. Most of these loci have not been studied systematically and the mechanistic underpinnings of risk are largely unknown. Here we explored the landscape of genomic features at an ER-negative breast cancer susceptibility locus at chromosome 2p23.2 and assessed the functionality of 81 SNPs with strong evidence of association from previous fine mapping. Five candidate regulatory regions containing risk-associated SNPs were identified. Regulatory Region 1 in the first intron of WDR43 contains SNP rs4407214, which showed allele-specific interaction with the transcription factor USF1 in in vitro assays. CRISPR-mediated disruption of Regulatory Region 1 led to expression changes in the neighboring PLB1 gene, suggesting that the region acts as a distal enhancer. Regulatory Regions 2, 4, and 5 did not provide sufficient evidence for functionality in in silico and experimental analyses. Two SNPs (rs11680458 and rs1131880) in Regulatory Region 3, mapping to the seed region for miRNA-recognition sites in the 3' untranslated region of WDR43, showed allele-specific effects of ectopic expression of miR-376 on WDR43 expression levels. Taken together, our data suggest that risk of ER-negative breast cancer associated with the 2p23.2 locus is likely driven by a combinatorial effect on the regulation of WDR43 and PLB1.


Assuntos
Neoplasias da Mama , Neoplasias de Mama Triplo Negativas , Neoplasias da Mama/genética , Estrogênios , Feminino , Predisposição Genética para Doença , Estudo de Associação Genômica Ampla , Humanos , Polimorfismo de Nucleotídeo Único
19.
J Food Sci Technol ; 58(12): 4693-4702, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34629533

RESUMO

ABSTRACT: The widely used methodology to quantify polyphenols-the Folin-Ciocalteu (FC) method-cannot be applied indiscriminately since different matrices may impair the assay's accuracy. Thus, this study aimed to adapt the FC method for the açaí seed extract, a tannin-rich extract with potential applications for various therapies. Firstly, a pre-method standardization was established to determine parameters such as reading wavelength (765 nm), reaction time (30 min), and the reference substance (pyrogallol). In the validation step, the adapted method responded linearly to the analyte (R2 = 0.9910), ensuring its selectivity (linearity and selectivity curves statistically parallel) and accuracy (99.18-101.43%). Furthermore, the method proved to be precise (RSD ≤ 2.63%) at the two levels assessed (repeatability and intermediate precision) and robust (RSD ≤ 4.45%) concerning variation on the Na2CO3 concentration and the reaction time. The limits of detection and quantification were also calculated (9.9 µg/mL and 33.1 µg/mL, respectively). An additional step for tannins quantification based on its reported selective precipitation by complexing agents was also evaluated; however, unspecific precipitation was observed, reducing the results' accuracy. Our work successfully adapted and validated a method for total phenolics quantification of açaí seed extract, resulting in 38 g of pyrogallol equivalent/100 g of extract.

20.
Cancer Epidemiol Biomarkers Prev ; 30(9): 1604-1606, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34475121

RESUMO

Despite recent notable treatment advancements, ovarian cancer survival rates remain poor, with about half of women surviving five years after diagnosis. Uncovering novel prognostic factors is critical to better understand and reduce mortality from this deadly disease. While genome-wide association studies have identified numerous loci associated with risk of epithelial ovarian cancer, the investigation of genetic factors associated with outcomes among women with ovarian cancer has been limited due to several challenges summarized in the present commentary. Using data from the Ovarian Cancer Association Consortium, Quinn and colleagues conducted a genome-wide association study of patients with ovarian cancer receiving debulking surgery and standard chemotherapy as first-line treatment, revealing a locus at 12q24.33 associated with progression-free survival. Experimental evidence suggests that ULK1, a gene coding for a serine/threonine kinase implicated in autophagy, is the target of the association. We discuss the novelty of these findings, unanswered questions, and next steps for the road ahead in translating the work of Quinn and colleagues into clinical practice.See related article by Quinn et al., p. 1669.


Assuntos
Estudo de Associação Genômica Ampla , Neoplasias Ovarianas , Carcinoma Epitelial do Ovário/genética , Feminino , Humanos , Neoplasias Ovarianas/genética , Intervalo Livre de Progressão
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